#include <ext/range.hpp>
#include <DB/Dictionaries/ExternalResultDescription.h>
#include <DB/DataTypes/DataTypesNumberFixed.h>
#include <DB/DataTypes/DataTypeString.h>
#include <DB/DataTypes/DataTypeDate.h>
#include <DB/DataTypes/DataTypeDateTime.h>


namespace DB
{

namespace ErrorCodes
{
	extern const int UNKNOWN_TYPE;
}

void ExternalResultDescription::init(const Block & sample_block_)
{
	sample_block = sample_block_;

	const auto num_columns = sample_block.columns();
	types.reserve(num_columns);
	names.reserve(num_columns);
	sample_columns.reserve(num_columns);

	for (const auto idx : ext::range(0, num_columns))
	{
		const auto & column = sample_block.safeGetByPosition(idx);
		const auto type = column.type.get();

		if (typeid_cast<const DataTypeUInt8 *>(type))
			types.push_back(ValueType::UInt8);
		else if (typeid_cast<const DataTypeUInt16 *>(type))
			types.push_back(ValueType::UInt16);
		else if (typeid_cast<const DataTypeUInt32 *>(type))
			types.push_back(ValueType::UInt32);
		else if (typeid_cast<const DataTypeUInt64 *>(type))
			types.push_back(ValueType::UInt64);
		else if (typeid_cast<const DataTypeInt8 *>(type))
			types.push_back(ValueType::Int8);
		else if (typeid_cast<const DataTypeInt16 *>(type))
			types.push_back(ValueType::Int16);
		else if (typeid_cast<const DataTypeInt32 *>(type))
			types.push_back(ValueType::Int32);
		else if (typeid_cast<const DataTypeInt64 *>(type))
			types.push_back(ValueType::Int64);
		else if (typeid_cast<const DataTypeFloat32 *>(type))
			types.push_back(ValueType::Float32);
		else if (typeid_cast<const DataTypeFloat64 *>(type))
			types.push_back(ValueType::Float64);
		else if (typeid_cast<const DataTypeString *>(type))
			types.push_back(ValueType::String);
		else if (typeid_cast<const DataTypeDate *>(type))
			types.push_back(ValueType::Date);
		else if (typeid_cast<const DataTypeDateTime *>(type))
			types.push_back(ValueType::DateTime);
		else
			throw Exception{
				"Unsupported type " + type->getName(),
				ErrorCodes::UNKNOWN_TYPE};

		names.emplace_back(column.name);
		sample_columns.emplace_back(column.column.get());
	}
}

}
